I'ver seen you post about that oil-in-the-water problem before. So, did the crankcase oil go down by 2 quarts, as the cooling system "gained" two quarts of "oil"? I sure am curious as to what's going on. Since this is a "flathead" engine, there is NO oil passage going anywheres near the cylinder head that could easily leak into the cooling system (OHV engines typically have an oil passage up through the block, matching up with a passage in the head, after passing through the head gasket, and then plumbed into the rocker arm shafts.) The closest pressurized oil gets to the water jacket is in the cam bearing area, matching up with the main bearing "webs". If the bottom side of the waterjacket has an unseen crack down into the pressurized oil gallery in the cam bearing area, that would POSSIBLY provide a passage for the oil to get into the water. Several times, there have been posts on here speculating about that, but I have never seen any information proving conclusively this can and DOES happen. It would have to be a TINY crack, allowing pressurized oil to leak one way, but little water to leak into the oiling system, under gravity, while the tractor is shut down for long periods. The other possiblilty is a casting flaw ("porous casting") that provides a passage from the cam bearing (bore) oiling area to the water jacket. I would think you could pull the head, fill the radiator and engine with water 'til the water level in the water jacket is near level with the head gasket surface, and then pressurize the oiling system with shop air through the port at the rear of the block where the brass fitting adapter for the oil gauge and filter screws in. Any leaks from the oiling system to the cooling system should show up as bubbles rising in the coolant, over the leak. Only problem is, could it be REALLY freaky, and only leak when the block is warm??? Please post back, if you figure anything out!
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